https://books.google.com/books?id=ZlJb23UyAnYC&pg=PA558&lpg=PA558&dq=Cambridge+glass+Cleo+pattern++asparagus+tray&source=bl&ots=EgPVfb0JFc&sig=B831XrLYEm3B7wqbvJPQQJLgspc&hl=en&sa=X&ved=0ahUKEwiD3urFiqHbAhVQXK0KHf7JAb0Q6AEIRTAJ#v=onepage&q=Cambridge%20glass%20Cleo%20pattern%20%20asparagus%20tray&f=false

Scroll down here to see your tray !! Its an asparagus tray or could also be used as a celery server !! The indent is for a sauce !! Evidently they were dainty eaters back then !!